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The Train Thread 3
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rob smith Send message Joined: 7 Mar 03 Posts: 22534 Credit: 416,307,556 RAC: 380 |
With the air activated, air operated brakes, used on freight trains there is a fair time delay between the brakes being applied to the first vehicle in the train and the the last vehicle in the train. Depending on the exact type of brakes used (there are two major type, each with a couple of sub-types) and the train length this delay can be from a second or two up to about 30 seconds or more before the brakes start to come on at the rear of the train, and then it takes time for the braking to build-up to its maximum. So, if the leading loco derails, but dos not break the brake air circuit it might be a few seconds between its derailment and the brake lines being broken (which cause an automatic full brake application) during which time the train will bunch up, and be more prone to the concertenering we see so often. Add to that, if one of the wagons really comes of the rails and decelerates abruptly (or stops "instantly") the crumpled mess is inevitable, even on good straight and level track. Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
With the air activated, air operated brakes, used on freight trains there is a fair time delay between the brakes being applied to the first vehicle in the train and the the last vehicle in the train. Depending on the exact type of brakes used (there are two major type, each with a couple of sub-types) and the train length this delay can be from a second or two up to about 30 seconds or more before the brakes start to come on at the rear of the train, and then it takes time for the braking to build-up to its maximum. So, if the leading loco derails, but dos not break the brake air circuit it might be a few seconds between its derailment and the brake lines being broken (which cause an automatic full brake application) during which time the train will bunch up, and be more prone to the concertenering we see so often. Add to that, if one of the wagons really comes of the rails and decelerates abruptly (or stops "instantly") the crumpled mess is inevitable, even on good straight and level track. All of this also depends on the presence of absence of an EOT (end of train device) or FRED. Modern EOT's are supposed to detect an emergency application of the brakes and immediately release the air pressure at the end of the train. If the engineer calls for emergency application, as the EOT is in radio contact with the lead locomotive it drops air pressure at the speed of light. All of this is complicated more if the train has DPU's (distributed power units) or helper locomotives. Part of the reason for the FRED is to replace the brakeman on the caboose, who had to tell the engineer when the air pressure at the rear was enough that the brakes were released. It is all extremely over complex, as it was added on to many times, and not how a system would be designed today, but it works and replacing it on all the rolling stock would be time and cost prohibitive. Of course as trains carry mixed weights on the cars, brake application will have very different effectiveness on a car by car basis. You expect loaded cars to pile into empties as the empties stop much faster. It is amazing how much of the time it works. |
Wiggo Send message Joined: 24 Jan 00 Posts: 36800 Credit: 261,360,520 RAC: 489 |
I'll believe this when I see it actually happen. Long train regulations coming? The Senate is aiming for a late April markup of the Railway Safety Act of 2023, which would further regulate railroads after the East Palestine, Ohio, disaster.But something certainly needs to be done Cheers. |
rob smith Send message Joined: 7 Mar 03 Posts: 22534 Credit: 416,307,556 RAC: 380 |
They will fight with their favourite weapon - inertia. It costs less than implementing the modifications, far less than lawyers to fight in court, and hey, the only loosers are the insurance companies.... Bob Smith Member of Seti PIPPS (Pluto is a Planet Protest Society) Somewhere in the (un)known Universe? |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
The insurance company bean counters predict the payouts and raise the policy premiums but that is hidden on the P&L. The shipper always pays and he charges the consumer. |
Wiggo Send message Joined: 24 Jan 00 Posts: 36800 Credit: 261,360,520 RAC: 489 |
This company just doesn't want to stay on the rails. Multiple Norfolk Southern train cars derail near Pittsburgh. Early reports say that the cars were empty and staid upright this time. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66342 Credit: 55,293,173 RAC: 49 |
I'll believe this when I see it actually happen. Some think this doesn't go far enough, some think the freight railroads which are all privately owned in the USA should be Nationalized once again similar to what the USRA was, but this time permanently like in Europe, let the companies run the trains, but have government own the land the tracks sit on(row), own the tracks, do the maintenance, and own the trains. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
Early reports say that the cars were empty and staid upright this time. A lot of RR's have problems with empties. They put them too far in the front. Just ask any model RR guy why he has to put weights in his cars to keep them on the tracks. |
Wiggo Send message Joined: 24 Jan 00 Posts: 36800 Credit: 261,360,520 RAC: 489 |
Not another 1. :-( Train carrying hazardous materials derails in rural Maine, residents warned to 'stay clear'. More details are expected soon. |
Wiggo Send message Joined: 24 Jan 00 Posts: 36800 Credit: 261,360,520 RAC: 489 |
It maybe over a year late and well over budget, but it has finally happened. First driverless metro train crosses Sydney Harbour underwater. Cheers. |
W-K 666 Send message Joined: 18 May 99 Posts: 19401 Credit: 40,757,560 RAC: 67 |
YouTube - The Telegraph - Train maker builds GWR King Class replica worth £20,000 A hobbyist built a replica of the GWR King Class steam train - and it could sell for up to £20,000. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66342 Credit: 55,293,173 RAC: 49 |
Pretty, and almost 331lbs too. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Grant (SSSF) Send message Joined: 19 Aug 99 Posts: 13854 Credit: 208,696,464 RAC: 304 |
That is an exceptional piece of work, a great example of quality workmanship. Grant Darwin NT |
Wiggo Send message Joined: 24 Jan 00 Posts: 36800 Credit: 261,360,520 RAC: 489 |
And there goes another 1. Train derails in Wisconsin near Mississippi River. More to follow, but there's all those rotten timber sleepers which is likely the cause. Havn't they heard of concrete sleepers over there? |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66342 Credit: 55,293,173 RAC: 49 |
The US Railroads need to be nationalized again, in WW1 it was the USRA, this time permanently and no selling off without a 75% vote... Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
Ban the diesel electric locomotive, the most efficient land cargo transport. https://abc7.com/locomotive-emissions-trains-pollution/13190302/ Me thinks we are decades away from the technology being possible other that an experiment. https://www.wabteccorp.com/locomotive/alternative-fuel-locomotives/flxdrive Duration of Full 4400 HP output 30-40 minutes https://s7d2.scene7.com/is/content/Caterpillar/CM20230103-cf67a-ad066 |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
When you run a loaded [100 tonne] rail car over the sleeper with the wheel flange doing the slicing, the result is the same wood or concrete. I think that track is E&LS track, a class 2 RR so it is allowed much worse standards than class 1 (passenger) RR. |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66342 Credit: 55,293,173 RAC: 49 |
Railroads in Europe are government owned, just privately run, but all electric(1500v DC, 3kv DC, 15kv AC, and 25kv AC). Europe though still uses buffer and chain couplers on their freight trains, the US, Canada, and Mexico use only the Janney coupler for freight unlike in the wiki that says "largely" which is old, but not as old as in Europe, only the brake hoses in a Janney coupler requires a person to hand couple each car by hand to another car or locomotive. Freight railroads in North America needs to become all electric, just like the Milwaukee Road used to be... Oh and the MLW had to buy most of the land it needed since it received few if any federal land grants... Yes a mixed consist, some diesel electrics and a pure electric up front, instead of buying new electrics they went with diesels starting in 1974 just after the Arab oil embargo of the US in October 1973. Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
Gary Charpentier Send message Joined: 25 Dec 00 Posts: 31009 Credit: 53,134,872 RAC: 32 |
All US RR going electric is a fine thing to say, but ... US RR run in places where there are no power lines to power the track. Do you build more overhead power lines to start wildfires in remote areas? How about where they can't be built because of wilderness designations? Are existing tunnels tall enough for overhead power? Same for bridges? Are there other utility lines too low over the track? Is there clearance on the side of the track to place the poles to hold the overhead lines? Who pays for it? Europe is a bit different in that it has a much higher population density, so services are much closer to the track. Again it is a fine thing to say but in practice it may not be possible for the price willing to be paid for it to happen. Remember US RR can't even get PTC installed! |
zoom3+1=4 Send message Joined: 30 Nov 03 Posts: 66342 Credit: 55,293,173 RAC: 49 |
The lines can be insulated as SCE is starting to do or be buried. If a railroad can go thru there so can catenary, which electric trains use, 3rd rail is dangerous. Catenary was strung up back way before 1950 on the MLW, so it should be less of a problem than diesels are. On existing tunnels, in the NW I think so, at least if they were built prior to 1974, otherwise a railroads track could be lowered making the tunnel taller or if the overhead rock burden was thin enough day lighted. Is the right of way wide enough, there is no simple answer as that depends on where one is at, in a tunnel it's bolted to the walls or ceiling. Population density is not the problem, yes it is in Europe, yet there is catenary on the Trans Siberian Railway in Russia, so Density is Bogus. All freight railroads in the US are private, this includes the land the tracks are on up to the tracks, the cars and locos and the railroad police. The main problem is they don't want to spend the money, the government could in a heartbeat, all railroads would need to meet this standard, the auto industry did, so why can't the railroads? Going back to non smog equipped autos or not going to electric ain't happening as the rest of the world is going electric. Florida is flooding in the south and that will take weeks if not months to go away, in the Tulare Depression in CA, Tulare Lake is growing bigger and stopping that is currently not an option, so flooding that part of the ancient lake bed of the central valley in CA is happening south of the Kings River. And above all, Government does not need to make a profit... Savoir-Faire is everywhere! The T1 Trust, T1 Class 4-4-4-4 #5550, America's First HST |
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